2027 ICD-10-CM Diagnosis Code I70.301Unspecified atherosclerosis of unspecified type of bypass graft(s) of the extremities, right leg

ICD-10-CM Codes›I00–I99›I70-I79›I70

ICD-10-CM I70.301
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

I70.301 is a billable ICD-10-CM diagnosis code for unspecified atherosclerosis of unspecified type of bypass graft(s) of the extremities, right leg. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 299 through 301. The code is restricted by the Medicare Code Editor to adult patients (age 15 through 124). Coders also document this condition as atherosclerosis of bypass graft of right lower limb. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Peripheral and visceral vascular disease.

I70.301 no longer risk-adjusts for Medicare Advantage: it mapped to HCC 108 under the retired CMS-HCC V24 model through payment year 2025 but maps to no category in the live V28 model. It still risk-adjusts in the PACE (CMS-HCC V22) category 108, ESRD (V21) category 108, and ESRD (V24) category 108 for payment year 2027.

Code Identity

ICD-10-CM Code
I70.301
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified atherosclerosis of unspecified type of bypass graft(s) of the extremities, right leg
Short Description
Unsp athscl unsp type bypass of the extremities, right leg
Parent Code
I70.30
Unspecified atherosclerosis of unspecified type of bypass graft(s) of the extremities

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI70-I79Diseases of arteries, arterioles and capillaries
CategoryI70Atherosclerosis
This CodeI70.301Unspecified atherosclerosis of unspecified type of bypass graft(s) of the extremities, right leg

Code EditsBilling

Medicare Code Editor checks that affect claim validity for I70.301.

Adult diagnoses
The Medicare Code Editor detects inconsistencies in adult cases by checking a patient's age and any diagnosis on the patient's record. The adult code edits apply to patients age range is 15–124 years inclusive (e.g., senile delirium, mature cataract).

Medicare Risk Adjustment (HCC)Billing

I70.301 no longer risk-adjusts for Medicare Advantage: it maps to no payment category in the live CMS-HCC V28 model, although it still risk-adjusts in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
Dropped in V28 see all codes that no longer risk-adjust
Prior Model (CMS-HCC V24)
HCC 108
V24 retired last contributed to a Medicare Advantage risk score in payment year 2025
Other CMS Models
PACE (CMS-HCC V22): HCC 108 · ESRD (V21): HCC 108 · ESRD (V24): HCC 108
ESRD V21 weights: 0.065 dialysis, 0.086–0.271 functioning graft · ESRD V24 weights: 0.073 dialysis, 0.074–0.287 functioning graft
Part D (RxHCC)
Not mapped
I70.301 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Atherosclerosis of bypass graft of right lower limb

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to I70.301: its own notes plus those printed at I70.3, I70, and Chapter 9. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From I70 Atherosclerosis applies to 246 codes
  • arteriolosclerosis
  • arterial degeneration
  • arteriosclerosis
  • arteriosclerotic vascular disease
  • arteriovascular degeneration
  • atheroma
  • endarteritis deformans or obliterans
  • senile arteritis
  • senile endarteritis
  • vascular degeneration

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From I70.3 Atherosclerosis of unspecified type of bypass graft(s) of the extremities applies to 40 codes
  • embolism or thrombus of bypass graft(s) of extremities (T82.8-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From I70 Atherosclerosis applies to 246 codes
  • arteriosclerotic cardiovascular disease (I25.1-)
  • arteriosclerotic heart disease (I25.1-)
  • atheroembolism (I75.-)
  • cerebral atherosclerosis (I67.2)
  • coronary atherosclerosis (I25.1-)
  • mesenteric atherosclerosis (K55.1)
  • precerebral atherosclerosis (I67.2)
  • primary pulmonary atherosclerosis (I27.0)
From Chapter 9 (I00-I99) Diseases of the circulatory system applies to 1,433 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • systemic connective tissue disorders (M30-M36)
  • transient cerebral ischemic attacks and related syndromes (G45.-)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From I70.3 Atherosclerosis of unspecified type of bypass graft(s) of the extremities applies to 40 codes
  • code, if applicable, to identify chronic total occlusion of artery of extremity (I70.92)
From I70 Atherosclerosis applies to 246 codes
  • code to identify:
  • exposure to environmental tobacco smoke (Z77.22)
  • history of tobacco dependence (Z87.891)
  • occupational exposure to environmental tobacco smoke (Z57.31)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name I70.301, its category, or a range that includes it.

Excludes1 3

These codes carry an Excludes1 note naming I70.301: they are not reported together with it, unless the two conditions are unrelated.

  • I77.6 Arteritis, unspecified
    deformans (I70.-) names I70.-, which includes this code
  • I77.6 Arteritis, unspecified
    obliterans (I70.-) names I70.-, which includes this code
  • I77.6 Arteritis, unspecified
    senile (I70.-) names I70.-, which includes this code

Code First 1

These codes say to code first a condition named in the note, and I70.301 is one of the conditions named.

  • I70.92 Chronic total occlusion of artery of the extremities
    atherosclerosis of arteries of the extremities (I70.2-, I70.3-, I70.4-, I70.5-, I70.6-, I70.7-) names I70.3-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR CIR026
Peripheral and visceral vascular disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Atherosclerosis

    a thickening and loss of elasticity of the walls of arteries that occurs with formation of atherosclerotic plaques within the arterial intima.

Patient EducationClinical

Atherosclerosis

Atherosclerosis is a condition in which plaque builds up inside your arteries. Plaque is a sticky substance made up of cholesterol, fat, blood cells, calcium, and other substances found in the blood. Over time, plaque hardens and causes your arteries to narrow. That limits the flow of oxygen-rich blood to your body.

The full article covers:

  • What is atherosclerosis?
  • What causes atherosclerosis?
  • Who is more likely to develop atherosclerosis?
  • What are the symptoms of atherosclerosis?
  • What other problems can atherosclerosis cause?
  • How is atherosclerosis diagnosed?
  • What are the treatments for atherosclerosis?
  • Can atherosclerosis be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert I70.301 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
440.30 Athscl extrm bps gft NOS
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About I70.301Overview

Is I70.301 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified atherosclerosis of unspecified type of bypass graft(s) of the extremities, right leg on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does I70.301 group to?

When unspecified atherosclerosis of unspecified type of bypass graft(s) of the extremities, right leg is the principal diagnosis on an inpatient stay, it groups to MS-DRG 301, 300, 299, with relative weights from 0.7132 to 1.5840 depending on complications. Higher weights mean higher Medicare reimbursement.

Who can I70.301 be reported for?

The Medicare Code Editor checks unspecified atherosclerosis of unspecified type of bypass graft(s) of the extremities, right leg against patient demographics: this code is intended for adult patients (age 15 through 124). Claims outside these limits are flagged as inconsistent.

Can I70.301 be reported with a code from T82.8?

Not as a rule. The Excludes1 note at I70.3, which applies to I70.301, lists "embolism or thrombus of bypass graft(s) of extremities (T82.8-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

Does I70.301 need an additional code?

When the condition applies, yes. The Use Additional Code note at I70.3, which applies to I70.301, reads: code, if applicable, to identify chronic total occlusion of artery of extremity (I70.92). The additional code is reported after I70.301.

Does I70.301 risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage. I70.301 mapped to HCC 108 in the retired CMS-HCC V24 model, which last determined payment in 2025, but it maps to no category in the live V28 model; see all codes that no longer risk-adjust. It still risk-adjusts in the PACE (CMS-HCC V22) category 108 (Vascular Disease), ESRD (V21) category 108 (Vascular Disease), and ESRD (V24) category 108 (Vascular Disease).